Device for connecting a motor with at least two electric conductor tracks

ABSTRACT

A pluggable adapter for connecting a miniature electric motor, especially of a central locking device of an automotive vehicle, with the end pieces of conductor tracks and to accommodate the motor in the housing. Soldering is no longer necessary and there aren&#39;t any disturbing cables.

TECHNICAL FIELD

The present invention relates to a device for the connection of aminiature electric motor with at least two electric conductor tracks ofa printed-circuit board, particularly with regard to the housing of acentral locking device of an automotive vehicle, the miniature motorpresenting one socket per conductor track end to be inserted.

BACKGROUND OF THE INVENTION

Today miniature motors are applied in connection with different servodevices. In the automobile industry there are many applications of suchservo devices, e.g. for opening and closing the windows or also foractuating a central locking device. The miniature motor or even severalminiature motors have to be connected in the designated way withconductor tracks of a printed-circuit board or the like.

Originally, each motor was provided with a cable connection and thecable was connected with the conductor tracks of the printed-circuitboard by plugging or soldering it. Attempts have also been made toconnect contact sheets of the motor with flat plugs. These connectionsare expensive and time consuming since they have to be realizedmanually. Furthermore it is often undesirable to lay cables in thehousing of the device because the cable can hinder the motion of themoving components. This applies especially when the device provided withone or more motors is exposed to vibrations, as is always the case inautomobiles.

In another known version, such miniature motors are provided with slideconnectors which protrude from the motor like the contact sheets do.These slide connectors are pushed into the openings of the conductortracks and soldered directly to them. Although in this case no cable isinvolved, the miniature motors must have a precisely defined position inrelation to the printed-circuit board or the conductor tracks inquestion. This defined position often does not correspond to the desiredmounting position of the motor. This is especially true when the motoris not provided with a circular, but an oval or similar non circularhousing. Furthermore the layout of the conductor tracks depends on theconformation of the motor. Modifications of the motor generally leads toa corresponding modification of the conductor tracks. This is timeconsuming and usually also very expensive.

The object of the present invention is therefore to develop the devicementioned at the beginning in such a way, that the motor can be mountedsimply and quickly despite the absence of a cable connection and thatsmall modifications of the motor do not involve any or at least anyimportant adaptation to the connection of the printed-circuit board.

This object is achieved according to the present invention by puttingthe adapter between the end pieces of the conductor tracks and socketsof the motor. This arrangement provides for an electrically conductiveconnection between the motor and the conductor tracks and permits thequick adaptation to a slightly modified motor and/or modified end piecesof the conductor tracks. In addition to this, the connection of themotor with the adapter as well as the connection of the adapter with theend pieces of the conductor tracks is pluggable, so that cables are nolonger necessary. The respective plug-in connections can be designed asalready known. Therefore the miniature motor, e.g. coupled with theadapter, can be connected easily, quickly and safely with the end piecesof the conductor tracks, or in the specific case, with the centrallocking device, all prerequisites for an automatic assembly being given.

In another improvement of the present invention, the ends of theelectrically conductive elements close to the motor are formed as plugpins which are retained in the sockets of the miniature motor in aclamped way. In this case the sockets have a flat plug-in opening inwhich the electrically conductive elements are plugged in an elasticallyclamped manner.

In another aspect of the present invention, the lateral distance of theends of the electrically conductive elements close to the motorcorresponds to the lateral distance of the sockets of the miniaturemotor so that both can be coupled by a linear motion and at the sametime be connected in an electrically conductive way.

For reasons of cost and weight, the material thickness of theelectrically conductive elements should be as small as possible. Stampedparts, however, must present a minimum thickness because of the stampingprocedure. If the sockets after a modification of the miniature motorare provided with somewhat wider insertion slots for the electricallyconductive elements, it may be possible that a tight fit of theelectrically conductive elements in the sockets can no longer beensured. In another embodiment of the present invention, an improvementis achieved in that the flat sides of the electrically conductiveelements are parallel and each one shows a depression, particularlyextending in the plug-in direction, which leads to enlarged ends ofthese electrically conductive elements to be inserted so that, at leastin case of elastically expanding sockets, also small dimensionaltolerances near the sockets can be compensated within certain limits.

The depressions of the two electrically conductive elements are directedtowards each other in a particularly preferred manner. Since the form ofthe two electrically conductive elements is, apart from that,essentially similar, the different position of the depressions withregard to their flat sides provides for a certain identification whichpermits an automatic sorting. This is the prerequisite for an automaticor at least semi-automatic assembly. As for the rest, the electricallyconductive elements can be retained in the base member of their adapterin one of the known ways, e.g. by jamming or by extrusion if theadapter, as foreseen in the present embodiment, is made of plasticmaterial.

Preferably, the electrically conductive elements have an essentiallyangular shape. This means that when the electrically conductive elementsabut loosely on a surface, one leg is parallel to the one of the otherelectrically conductive elements and their depressions point upwards,the other leg points into the opposite direction. This can be exploitedfor the identification of the single parts.

As already mentioned, the electrically conductive elements can beplugged into the base member or extruded with its material. In a variantof the present invention, preferred in this regard, clamping engagementis easily achieved by the depression, nipple provided the insertion slotor the material in this area is sufficiently yielding so that thedepression or nipple can penetrate to some extent. A favorable variantis also to clamp the electrically conductive element by means of a snapconnection in which the nipple snaps in behind a projection or undercut.

As already mentioned, the adapter and the end parts of the conductortrack can be connected in a pluggable manner. In to ensure that thisplug-in connection is vibration proof and to secure it, it is advisableto make each end piece of the conductor track engage between two forkprongs on the leg of the angle which is remote from the motor. Thelength of the parallel part of the fork prongs and therefore theconstant width of the insertion slot corresponds to the width of theconductor track.

A particularly preferred variant of the present invention ensures thatthe unit consisting of the adapter and the miniature motor can beslipped onto the end pieces of the conductor track by a simple linearmovement which permits a fully automatic assembly and excludes wrongelectrical connections in each of the two connecting points.

In order to ensure a safe electrical connection between the end piecesof the conductor track and the adapter or its electrically conductiveelements, an enlargement at the insertion end of each end piece of theconductor track is provided for, in particular a depression extending inthe plug-in direction, which is associated with the space between theparallel parts of the fork prongs. By this it is also possible toachieve a tight mechanical connection which certainly leads to a highelectrical safety of these connecting points.

Developments being of particular advantage to the fully automaticconnection of the adapter or the unit consisting of adapter andminiature motor with the end pieces of the conductor track, aredescribed. First of all, the insertion slopes permit a safe connectionbetween the adapter and the end pieces of the conductor track even ifthere is a slight deviation from the correct position. By means of theinsertion slopes, they are introduced safely into the insertion slots onthe inside of which are positioned the forks of the two electricallyconducting elements which are coupled mechanically and in anelectrically conductive manner to the end pieces of the conductor trackwhen the adapter is slipped onto these end pieces.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is the top view of a central locking device of the presentinvention with fitted miniature motor which is connected electrically bymeans of the device being object of the present invention, the coverbeing partly broken away.

FIG. 2 is a top view of the adapter surface close to the motor withfitted electrically conductive elements, on an enlarged scale.

FIG. 3 is a cross-sectional view of FIG. 2 taken along line III--III.

FIG. 4 is an enlarged view of an electrically conductive element.

FIG. 5 is a front view of this element, partly cut along line V--V.

FIG. 6 is a top view of the other electrically conductive element.

FIG. 7 is a representation corresponding to FIG. 5, partly cut alongline VII--VII of FIG. 6.

FIG. 8 is a representation according to FIG. 2 without the electricallyconductive elements.

FIG. 9 is a cross-sectional view along line IX--IX of FIG. 8.

FIG. 10 is a side view of the adapter in the direction of arrow X ofFIG. 8.

FIG. 11 is a view of the adapter in the direction of arrow XI of FIG.10.

FIG. 12 is a view of the adapter in the direction of arrow X of FIG. 8.

FIG. 13 is a view of the adapter in the direction of arrow XIII of FIG.12.

FIG. 14 is a cross-section along line XIV--XIV of FIG. 13.

FIG. 15 is a cross-section along line XV--XV of FIG. 8.

FIG. 16 is a cross-section along line XVI--XVI of FIG. 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the housing 1 of a central locking device for an automotive vehicle,there is a miniature electric motor 2 driving a worm 3. This worm mesheswith a worm wheel 4. According to the present invention, the miniatureelectric motor 2--hereinafter referred to as "motor"--is connected in anelectrically conductive way with two electrical conductor tracks 6 and 7by means of an adapter 5, the conductor tracks being attached to aprinted-circuit board 8 which is not represented in detail and which inthis embodiment is fixed at the bottom on the inside of the devicehousing 9 or is made of the bottom itself being the carrier of thepunched conductor tracks. The device housing 9 is closed to the outsideby means of a cover 10. The end pieces of the conductor tracks on whichin FIG. 1 the adapter 5 is slipped perpendicularly from above to thebottom, extend therefore from the bottom of the housing 1perpendicularly towards the top and the person who looks at the drawing.

In FIGS. 8 to 14 the adapter 5 is represented in detail. FIGS. 2 and 3show the adapter 5 equipped with the electrically conductive elementswhich are represented on an enlarged scale in FIGS. 4 to 7.

According to e.g. FIGS. 10 and 12, the adapter 5 is essentiallybow-shaped or groove-shaped. This depends on the motor 2 showing aregular cylindrical section with two parallel flat portions and theadapter 5, according to FIG. 12, being attached to one of these flatportions. Its two legs 11 and 12 each are associated with one of thecurved housing walls or encompass these in part.

The electrically conductive elements 13 and 14 showing, according toFIGS. 4 and 6, an essentially angular shape, in the present embodimentare simply plugged into the base member 15 of the adapter 5, but couldalso be embedded into the plastic material of the base member 15, i.e.extruded by it. From FIGS. 4 and 6 further discloses electricallyconductive elements having a different size. With regard to thegeometrical dimensions, leg 16 of the electrically conductive element 13corresponds to leg 17 of the electrically conductive element 14. Eachleg 16 or 17 is provided with a depression 19 or 20 extending in itslongitudinal direction and therefore also in the direction 18 in whichthe adapter 5 is slipped on the motor 2. In FIGS. 4 and 6 theprojections of the depressions are pointing upwards, i.e. towards theperson who looks at the drawing. When mounted, the ends 21 or 22 of theelectrically conductive elements 13 and 14 being close to the motor,point in the same direction so that the two depressions 19 and 20 aredirected towards each other. This explains why the arrows for theslip-on direction 18 are opposite to each other in FIGS. 4 and 6.

Approximately in the transition point from one leg 16 or 17 to the otherone 23 or 24 there is a further indentation or depression 25 or 26 whichin the embodiment is circularly limited on the outside. It extends inrelation to the depression 19 or 20 in the opposite direction, i.e. inFIG. 4 or 6 downward, and serves for clamping the referred electricallyconductive elements 13 or 14 in the base member 15 by means of a snapconnection which will subsequently be described more in detail.

The free end of the other leg 23 or 24 has a forked shape, i.e. it isprovided with an open slot 27 or 28. In order to form a throat, the freeends of the fork prongs 29 and 30 are deflected towards each other orthe sides of the slot are bulged towards the inside. In FIG. 4 thethroat is indicated with 31.

Every leg 16 or 17 of the electrically conductive element 13 or 14provided with a depression 19 or 20 projects from the surface 32 of thebase member 15 of the adapter 5 being close to the motor 2 or adjacentto it and extends also perpendicularly to this surface. Both legs 16 and17 are parallel to each other and thus also to the drawing plane andprotrude from the surface 32 to an equal extent. Each leg can beinserted into a socket of the electric motor 2 which is not illustrated,the depression 19 or 20 providing for a good electrical contact and aretaining of the adapter 5 by jamming it to the motor 2. The sockets areprovided with a slot and can also be formed, e.g., by a U-formedelement, leg 16 or 17 engaging between its legs.

When the adapter is mounted, the end piece of the conductor track,indicated with 33 in FIG. 3, is positioned inside the throat 31, i.e. atthe point where the open slot 27 or 28 is limited by two parallelborders. In FIG. 3 it extends perpendicularly to the drawing plane. Thismeans that the adapter 5 being fixed to the miniature electric motor isslipped, perpendicularly to the drawing plane in FIG. 3, from above tothe bottom onto the end pieces of the conductor track. In order toillustrate this, in FIG. 3 also the other end piece of conductor track34 is drawn with a dashed line. But it does not extend upward as much asthe end piece of conductor track 33, because the electrically conductiveelement 14 with the shorter leg 24 that is remote from the motor, ispositioned underneath leg 23. In FIG. 3 can also be seen why the otherleg 24 is shorter than leg 23 of the electrically conductive element 13.The distance between the electrically conductive elements 13 and 14 canbe learned from FIG. 2.

At the plug-in or push-in end of each end piece of the conductor tracks,32, 34, there is an enlargement (a depression) extending in the plug-indirection, which corresponds to depression 19 or 20 of the electricallyconductive elements 13, 14. For the sake of clarity it is not indicatedin FIG. 3. This depression is exactly associated with the forked area ofthe electrically conductive elements, so that the fork prongs can beexpanded elastically providing a good mechanical and electricallyconductive contact.

The other leg 23 or 24, which is remote from the motor, is inserted in aslot 35 or 36 (FIGS. 12 and 3) and retained in this slot by clamping itwith depression 25 or 26, the slot having an angular form according toFIG. 3, so that the whole electrically conductive element 13 or 14, withthe exception of the free end of leg 16 or 17, is entirely accommodatedin the base member 15 made of plastic material and is therefore storedsafely from an electrical point of view.

Each slot 35 and 36 is crossed by another slot 37 or 38 (FIG. 12).Furthermore each slot accommodates an end piece of a conductor track.The open slot 27 or 28 of the leg 23 or 24 remote from the motor, is inalignment with the slot 37 or 38 so that the end pieces of the conductortracks can be pushed through in the direction of arrow 39 when theadapter 5 is mounted. In practice, however, the adapter 5 with theelectric motor 2 will be slipped onto the end pieces of the conductortracks, 33, 34, in the opposite direction to arrow 39. In order topermit a good insertion of the end pieces of the conductor track, theend portion, i.e. at the point where slot 37 passes into slot 38, isprovided with insertion slopes 40, 41. Certainly, slot 38 in directionof arrow 39 is shorter than slot 37 which has to accommodate the longerend piece of conductor track 33. According to FIG. 13, this is also truefor the slots 35 and 36.

FIG. 12 indicates also shoulders 42 which engage in correspondingrecesses of the motor housing and therefore improve safe positioning aswell as mounting. A center groove 43 can engage with a spring shaped atthe motor housing.

From the above details, it can be easily seen that the two electricallyconductive elements 13 and 14 can be identified by means of a sortingdevice and the above mentioned identification and can be inserted intothe base member 15 or into the foreseen slot in fully automatic way.However, it is not only possible to mount the electrically conductiveelements 13 and 14 to the adapter 5 in fully automatic way, but also toslip the adapter automatically onto the electric motor 2. Finally, theunit consisting of the miniature electric motor 2 and the adapter 5 canalso be slipped onto the end pieces of the conductor tracks, 33 and 34,in an automatic procedure. This leads without doubt to a reduction ofthe assembly costs and contributes to an increased production and areduced rejection rate. Small modifications of the miniature electricmotor can be compensated easily by modifying the base member 15 and/orthe electrically conductive elements 13, 14, slight changes at theplug-in sockets of the electric motor being compensated, if necessary,already only by the depressions 19 and 20 of the electrically conductiveelements 13, 14.

Often the electric motor 2 does not have a circular, but a non circularcross-section. By means of adapter 5, designed in the form describedabove, such a motor can be mounted on edge in housing 1 of the centrallocking device and thus be accommodated saving much space.

I claim:
 1. Device for connecting a miniature electric motor to at leasttwo electric conductor tracks of a printed circuit board, said miniaturemotor being provided with one socket for each end piece of each of saidelectric conductor tracks, said end pieces of said conductor tracksprojecting substantially vertically from a plane of said printed circuitboard, said device comprising an adapter between said miniature electricmotor and said printed circuit board, said adapter being formed of abase member and at least two electrically conducting elements, said basemember of said adapter including a slot extending in a direction inwhich it is slipped onto said end pieces of said conductor tracks, saidend piece of each of said conductor tracks electrically connected to arespective socket of said miniature electric motor through saidelectrically conducting elements, end portions of said electricallyconducting elements proximate to said motor forming flat plug pinsretained in said sockets, wherein end portions of said electricallyconducting elements, remote from said motor, cross said slot.
 2. Deviceas claimed in claim 1, wherein the electrically conductive elements areretained in the base member of the adapter by means of a snapconnection, each of said elements being provided at least with oneprotruding depression means, which extends transversely relative to itsplane.
 3. Device as claimed in claim 2, wherein the electricallyconductive elements have angular shape.
 4. Device as claimed in claim 3,wherein the electrically conductive elements are inserted into the basemember of adapter in the longitudinal direction of the leg which isremote from the motor.
 5. Device as claimed in claim 4, wherein theelectrically conductive elements are retained in the base member of theadapter by jamming them, each of said elements being provided at leastwith one protruding depression means which extends transversely relativeto its plane.
 6. Device as claimed in claim 3 wherein the leg of theangle of each electrically conductive element which is remote from themotor, has a fork-like shape.
 7. Device as claimed in claim 6, whereinfree ends of the two fork prongs are shaped in order to form a throat.8. Device as claimed in claim 7, wherein the motor with the adapter isslipped onto the free end pieces of the conductor track perpendicularlyto the plane of the electrically conductive elements, which are parallelto each other.
 9. Device as claimed in claim 8, wherein at the insertionend of each end piece of the conductor tracks there is an enlargementshaped as a depression which is associated with a slot between theparallel parts of the fork prongs, said depression extending in thedirection parallel to said parallel parts.
 10. Device as claimed inclaim 9, wherein said slot provided in the base member of the adaptercrosses the slots foreseen for said end portions of the electricallyconductive elements which are remote from the motor, the slots betweenthe parallel parts of the forked prongs being positioned betweensections of said slot in the base member.
 11. Device as claimed in claim10, wherein the slots at their end for the insertion of the end piecesof the conductor tracks are expanded in order to form insertion slopes.12. Device as claimed in claim 11, wherein the conductor tracks arefastened at the bottom of the housing of the central locking device andthe flat end pieces of the conductor tracks extend parallel to a sidewall of the housing, pointing to a housing cover.
 13. Device as claimedin claim 1, wherein said end portions of the electrically conductiveelements close to the motor project from a surface of the adapter, facethe motor, and are parallel to each other and perpendicular to saidsurface.
 14. Device as claimed in claim 1, wherein said end portions ofsaid electrically conducting elements forming flat plug pins areparallel to each other, each one presenting a depression extending inlongitudinal direction of said end portions.
 15. Device as claimed inclaim 14, wherein said depressions point toward each other.
 16. Deviceas claimed in claim 15, wherein the adapter and the motor are arrangedadjacent to each other.
 17. Device as claimed in claim 6, wherein theadapter has a bow-shaped design, two bow legs which protrude in theslip-on direction encompassing a housing of the motor on the outside.